Twist Beam Axle with Integral Torsion Bar

Abstract

A traditional twist beam axle found in a vehicle includes a twist beam with a separate torsion beam or a hollow tube formed into an inverted U shape that acts as both the twist beam and the torsion beam. Both solutions are expensive to manufacture A twist beam axle ( 14 ) is provided wherein the torsion member ( 42 ) is rigidly secured to the twist beam ( 40 ) The twist beam ( 40 ) has a U-shaped cross-sectional configuration having a bight portion ( 44 ) with first ( 50 ) and second ( 52 ) projections extending therefrom Embodiments include the cross-sectional configuration having an open cavity and the bight portion ( 44 ) having an indentation into the open cavity and forming a depression that is covered by the torsion member ( 42 ) A method of forming the disclosed twist beam axle ( 14 ) is also provided, the method including the step of rigidly securing the torsion member ( 42 ) to the bight portion ( 44 ) of the twist beam ( 40 )

1 . A twist beam axle comprising:
 a twist beam having an inverted U-shaped cross-sectional configuration and a longitudinal extent, said cross-sectional configuration having a bight portion, and   a torsion member rigidly secured to said bight portion.   
   
   
       2 . A twist beam axle according to  claim 2 , wherein said torsion member is welded to said twist beam. 
   
   
       3 . A twist beam axle according to  claim 2  wherein said torsion member is seam welded to said twist beam. 
   
   
       4 . A twist beam axle according to  claim 3 , wherein said torsion member extends substantially along said bight portion. 
   
   
       5 . A twist beam axle according to  claim 4 , wherein said twist beam has a longitudinally extending groove and said torsion member closes said groove defining a hollow channel. 
   
   
       6 . A twist beam axle according to  claim 4 , wherein said twist beam has a longitudinally extending groove and said torsion member has a longitudinally extending groove and said torsion member closes said grooves defining a hollow channel. 
   
   
       7 . A twist beam axle according to  claim 4 , wherein said torsion member has a longitudinally extending groove and said bight portion closes said groove defining a hollow channel. 
   
   
       8 . A twist beam axle according to  claim 4 , wherein said twist beam has a first projection and a second projection extending from opposite side edges of said bight section defining said inverted U-shaped cross-sectional configuration and each of said first and second projections is curved. 
   
   
       9 . A twist beam axle according to  claim 1 , wherein said torsion member is separately formed member with respect to said twist beam. 
   
   
       10 . A twist beam axle according to  claim 1 , further comprising:
 a first arm coupled to a first end of said twist beam, said first arm having a wheel hub attaching member; and   a second arm coupled to a second end of said twist beam, said second arm having a second wheel hub attaching member.   
   
   
       11 . A method of forming a twist beam axle assembly, comprising:
 forming an elongate twist beam having an inverted U-shaped cross-sectional configuration defining an open section;   forming an elongate torsion beam; and   rigidly securing the torsion beam to a bight portion of the twist beam.   
   
   
       12 . A method according to  claim 11 , wherein the step of rigidly securing the torsion member to the bight portion includes welding the torsion member to the bight portion. 
   
   
       13 . A method according to  claim 12 , wherein the step of forming the twist beam includes forming a groove in the bight portion that projects into the open section, and the step of rigidly securing the torsion beam including positioning the torsion beam to extend over the groove. 
   
   
       14 . A method according to  claim 13 , wherein the step of forming the torsion beam includes forming a torsion beam groove, and the step of rigidly securing the torsion beam including positioning the torsion beam groove to extend over the twist beam groove. 
   
   
       15 . A method according to  claim 13 , wherein the step of forming the torsion beam includes forming a torsion beam groove, and the step of rigidly securing the torsion beam including positioning the torsion beam groove to extend over the twist beam. 
   
   
       16 . A method according to  claim 12 , wherein the step of forming the elongate twist beam is roll forming. 
   
   
       17 . A method according to  claim 16 , wherein the torsion member is welded during the roll forming step. 
   
   
       18 . A method according to  claim 17 , wherein the welding is seam welding. 
   
   
       19 . A method according to  claim 18 , wherein the seam welding is resistance seam welding. 
   
   
       20 . A method according to  claim 12 , wherein the torsion beam is rigidly secured to the twist beam along an interface therebetween. 
   
   
       21 . A method according to  claim 20 , wherein the torsion beam is rigidly secured to the twist beam by resistance seam welding.